Can't install version 0.5.0
There's an issue with the package listing on Foundry's site (i.e. https://foundryvtt.com/packages/tinyd6) where the Manifest URLs are pointing to the GitLab page for the manifest.json
file, which is an HTML page, instead of the raw file. Instead of https://gitlab.com/architech99/foundry-tinyd6/-/blob/36ffe3aa99d3000b88956cd8c832e434f04b4eac/system.json it should be https://gitlab.com/architech99/foundry-tinyd6/-/raw/36ffe3aa99d3000b88956cd8c832e434f04b4eac/system.json
I used the latter to install by URL and it works. But if you install from the package listing, it won't.